What is GMS:

  • Google Mobile Services - Probably not
  • Geographic Messaging Service - Don’t know of anyone using that yet
  • GMS - They appear to be a service provider

So, nothing that I can find that relates to a messaging standard.

So why does the Quectel EP06 AT Commands Manual have a complete section on Short Message Service Commands. That kinda suggests they do support it.

Sending an SMS from the XE300 works fine, as I receive that on my phone, which proves they DO support SMS. (Albeit I get the message twice, but hey, it still works). Responding to the message shows as a message received, so something understands the reception, but trying to read it gives all the issues documented above.

Cheers.